District of cqium



July 31, 1923.v

F. K. DAVHS ET AL.

ACOMBINED TYPEWRITING AND COMPUTING MACHNE 5 Sheds-Sheet l Filed Nov.2l, 1921 ZM M @M July 31, 1923. 1,463,155

F. K. DAVIS ET AL COMBINED TYPEWRITING AND COMPUTING 4MACHINE Filed NOV.2l 1921 3 Sheets-Sheet 2 v iisg.'

July 31, 1923.

F. K. DAVIS ET AL COMBINED TYPEWRITING AND COMPUTING MACHINE Filed Nov.21 1921 3 Sheets-Sheet 5 time ,FRANK K. DVES AND CHARLES (C. TAYLR, @FWEHNGTN, DSTRICT @E CLTUM= NEW?" YORK,

CMINED TYEEW'RLNG AND @@MU'TNG- LACHINE.

Application nlcd November To all 'whom t may concern:

Be it known that we, Freinr, l. Davis and CHARLES C. TAYr/on, bothcitizens et the United States, and residing in the city of Washington,District of Columbia, have invented certain new and useiul llmprovementsin Combined Typewriting and Cornputing Machines, of which the followingis a specification.

This invention relates to combined writing and computing` machines,settable 'l he two latch members or links are c for addition orsubtraction, and more particularly to state controlling means effectiveduring the return orbaclrward movement or the carriage, and is hereinillustrated as applied to a bookkeepingT machine of the Underwood-Hansontype.

ln a bookkeeping machine of the type referred to, the computing`mechanism, which is normally set for addition, may be set forsubtraction byV the rearward movement of a subtraction bar extendingtore and att. The rearward movement of the subtraction bar is usuallyeffected by a spring, and, when the machine is set for addition, thesubtraction bar is held in its :forward position by a hook or catchengaging in a notch in the bar. The release o the subtraction bar fromthe catch may be elected by a subtraction key connected to the catch soas to move therewith in both directions.

.The machine is motor-operated and both the motor-operation andsubtraction-setting may be efected by spring-urged levers having theirrear ends normally engaged by the outer ends ot transverse latch membersor links which restrain the respective levers `from operating under theaction ot their springs. rlllhe lever for releasing the snbtraction barhas a one-way connection with the catch which normally restrains the edby suitable trains of mechanism 'i' vers pivoted at the rear o ma thattappets projecting upw-irdly may be engaged respectively by @dosubtraction stops ci' the usual tioned on the carriage in accorti/ancecomputing Zones determined by the Each ot the tappets is beveled n thesi l' gagged by the stops during movement of the earring on thecorresponding lem? yield with reference t- 2l, '5.921. Serial No.536,625.

by the stops in such movement, but, upon engagement by astop movinginthe opposite direction, will swing on, itspivot and allow the passageot the stop without operation ot the corresponding lever. Actuation ofeither one of 'these levers by a suitable stop will cause respectivelyeither actuation ot the .general operator by the motor orsubtraction-setting by means of the subtraction bar.

such machines, controlling ot the state tor addition or subtraction isetlected automatically in the letter-feeding movement of the carriage,but no such control is eiiected during the return movement thereof.Actuation of the general operator by the motor will reset the machine toaddition, it set for subtraction, and it has been proposed to modify thetappet on the motor-trip lever and its connection with the latter, sothat the motor-trip lever will be actuated by the stop moving in eitherdirection, whereby, upon backing the carriage in a computing zone, the

motor-trip will be actuated and the machine,

it set tor subtraction, will be reset for addition. According to thisarrangement, the motor is actuated every time the carriage is backedinto a computing zone.

The main object ot the present invention is to provide means whereby, ifthe carriage is backed into a computing zone when the machine is set'for subtraction, the motortrip will be actuated and the machine resetto addition, but, in case the machine is set for addition, themotor-trip will not be ac-` Pta Y in lever, and, upon movement oie theiinl; iny i ine'dective position permit subtree"*onn setting, the hoolrwill passinto i i the linll it trie trip lever connected therewith inactuated position.

The hook or latch has a movable mounting which is normally maintained bythe general operator in position to enable the latch to enter the notchand to co-operate with the link or latch to hold it against movement.Upon forward movement of the general operator, the mounting will,however, be shifted so as to move the hook or latch away from the link,thereby permitting vthe link and the subtraction-trip lever to return totheir normal positions.d lVhen, therefore, the machine has been set forsubtraction, the tappet on the motor-trip lever will be locked againstyielding when engaged by the stop in a backward or return movement ofthe carriage, and, upon backing the carriage into a computing zone, themotor will be tripped and the general operator actuated, thesubtraction-trip lever then being released and permitted to return toits normal position, and consequently the tappet on the motor-trip leverwill be released.

If the subtraction-setting is eected by the subtraction key, provisionmust be made of means to aetuate the subtraction-trip lever. so as tolock the tappet on the motortrip lever toenable the machine to berestored to addition when backed into a computing zone. To this end,provision may be made of means actuated by the subtraction bar in itsrearward movement, whereby the link or latch connected with thesubtractiontrip lever will be moved to ineffective position by thesubtraction-setting bar, and then released, the link being maintained inthis ineffective position by the hook or latch arranged to, engage inthe notch therein, as in the case of automatic setting for subtraction.Upon backing the carriage into a computing zone, the motor-tripleverwill be actuated and the general operator will effect re-setting of themachine for addition in the usual manner.

Other features and advantages will hereinafter appear.

In the accompanying drawings,

Figure 1 is a diagrammatic side view, partly in section, of anUnderwood-Hanson machine with the invention applied thereto.

Figure 2 is a skeleton perspective view of the arts embodying theinvention.

Figure 3 is a view of the subtraction-trip and motor-trip levers, partof the subtraction-trip lever being broken away to show the means forAlocking the tappet on the motor-trip lever against pivotal movement withrespect thereto.

Figure 4 is a top view of the parts shown in Figure 3.

Figure 5 is a rear view of certain of the parts, showing them in normalposition.

Fi ure 6 is a view similar to Figure 5, but s rowing the position of theparts after position b actuation of the subtraction-trip lever by asubtraction-stop.

Figure 7 is a. detail view, partly in section, showing the link,connected with the subtraction-trip lever, and means for control-` lingthe same, the parts being in their no1'- mal positions.

Figure 8 is a view showing the latch, or hook, which is normally held inretracted the transverse link, positioned in the notc of the link andholding the latter in ineffective position.

Figure 9 is a detail view similar to Figure 8, but showing the parts inthe position assumed when the general o erator moves forward` thetransverse link eing released from the latch or hook.

Figure 10 is a detail view'showing the manner in which the motor-triplever is actuated upon backing the carriage into a computing zone whenthe tappet on said lever is locked against pivotal movement thereon as aresult of the previous actuation of the subtraction-trip lever.

Depression of numeral-keys 10 and alphabet-keys 11 will actuatekey-levers 12and bell-cranks 13 to swing type-bars 14.- upwardly andrearwardly' to canse types 15 thereon to co-operate with a platen 16 andeilect printing on work-sheets carried by the latter. The platen 16 isrotatably mounted in a carriage 17, supported on front and rear rails 18and 19, respectively` and urged in the letter-feeding direction bysuitable means (not shown).

The movement of the carriage under the action of its urging means iscontrolled by means of a rack 20, connected with the carriage andmeshing with a pinion 21, having the usual one-way connection with anescapement-wheel 22. As any one of the type-bars approaches the end ofits printing stroke. a shoulder 23 thereon will engage a universal bar24 and actuate the usual fast and loose dogs 25 and 26, respectively`thereby permitting movement of the escapement-wheel Q2, and,consequently, a letter-space movement of the carriage 17.

Provisin is made at the rear of the carriage of a rod 27, on which oneor more selectors Q8 may be loosely pivoted` so as to be slidabletherealong, and of a notched bar 29, with which a tooth 30 on eachselector co-ope'rates, so as to hold the selector in adjusted position.Each selector 28 is held in raised or effective position while passingthrough a computing Zone by means ot' a frusto-conical roller 31 thereonengaging a cylindrical roller 32, having tapered ends. thereby causing atappet or dog 33 on the selector to engage seriatim the forward ends ofjacks 34.-, pivote-d at 35 in ay housingr 3G. The movement of the jacks34 is transmitted, by means of thrust-links 37. levers 38.transposition-linkages 39 and bell-cranks 40.

lill) to pins or lugs 41 on pin-bars or denominational members 42,thereby advancing the latter seriatim, to enable digits to be indexedthereon, by depressing index-pins 43 carried thereby.

For the purpose of setting the index-pins 43, each of the numeral-keysfrom l to 9, inclusive, is provided with a pendant or thrust-link 44,which, upon depression, engages an arm 45 on a corresponding shaft 46 ofa set corresponding in number to the links 44, to actuateJ correspondinglinkage and causea pin-setting bar 47 `thereof to engage and depress apin, of the same value as the numeral-key depressed, on a pin-bar whichhas been advanced from its normal position, to bring the pins thereon inalignment with the pin-setting bars 47. This action is repeated eachtime-a digit is indexed in a different denomination.

Then the indexing of the number has been completed, the generaloperator48 may be actuated, to cause the bar 49, thereon to engage the depressedindex-,pins 43 and advance the pin-bars 42, in accordance with thesetting of the index-pins 43, therebactuating dial-wheels 50, suitablygeare to said bars 42, thedial-wheels 50` fomin part of a register, fromwhich the results o the computations may be read through a sight-openlng51 in the casing 52 of the computing mechanism. c

Manual. actuation of the general operator may be effected by means of ahandle 53, fixed on a shaft 54, the movement of the latter beingtransmitted by means of toothed sectors 55, fixed thereon, and'pinions56 to racks 57, forming parts of the general operator 48. The generaloperator may also be operated by motor-actuated means which may be, ingeneral, the same as disclosed in the patent to Wood, No. 1,299,646,dated April 8, 1919. To throw the motor-actuated means into operation,apin 58 may be raised vby means of a lever 59, pivoted at 60 andnormally held by a spring (notshown) in position to maintain the pin 58in its normal depressed position. Operation of the lever 59, to raisethe pin 58 to ineffective posltion, thereby releasing the rotatableclutch-member 61, may be effected by' depressing- 'the outer end oflever 59 by means of a motorstarting slide 62.

The machine may be set for subtraction by l means of a subtraction-key63, connected by means of a link 64 with an arm 65, fixed on atransverse shaft 66, which carries 'al hook or latch-member 67, normallyengaging a shoulder 68 at the forward endof a notch 69 in the usualsubtraction-bar 70. Upon operating the subtraction-key 63, the latchmember 67 will be moved to ineffective position, and the subtraction-bar70 will be moved rearwardly by its spring 70% thereby setting themachine for subtraction. fr pin 71 on the-bar 70 extends into a slot inone arm 72 of a bell-crank, the other arm 73 of which is connected by apin-and-slot connection 74 with an arm 75, fixed on a plate 76, pivotedat its upper edge and having its lower edge projecting into slots 77 inshafts 46.

Upon the rearward movement of the subtraction-bar 7Q, the plate 76 willbe turned in a clockwisedirection, and the shafts 46 moved forwardly, tochange the connections betweenI the shafts and the pin-setting linkagesin the usual manner. The rearward movement of the subtraction-bar 70will also effect setting of the 9 pins in the usual manner. After thecompletion of the indexing of a number, when the mechanism is set forsubtraction, the pin-bars may be advanced by the general operator, andsubtraction effected by the complemental method. 1n the forward movementof the general operator, the bar 49 thereof will engage a. lug 78 on thesubtraction-bar 70 and advance the same to a position to enable the hookor latch-member 67 to engage the shoulder 68 and retain thesubtraction-bar in its forward position.

lln order to effect automatic control of the motor and thesubtraction-setting means, use is made of' addition-stops 80 andsubtractionstops 81, settable on a notched bar 79 supported on the rearof the carriage. Each stop of the two kinds is made up of two parallelspaced plates, and, as here shown, the right-hand plate, looking fromthe front of the machine, 1s provided witha downward extension 82toco-operate with a usual tabulator-plunger or counter-stop 83. Thedownward extension 82 of each of the stops is also utilized in trippingthe motor, and, in passing out of a computing zone in a letter-feeddirection, engages the beveled side 84 of a dog or tappet 85 pivotallymounted on a motor-trip lever 86. When engaged by the downward extension82 as the carriage moves in a letter-feed dirertion, the dog 85 is heldagainst movement on its pivot by engagement with a stop or abutment 87on I the lever and the latter is operated. Upon engagement of theleft-hand beveled face 88 of the dog 85 in the return movement of thecarriage, the dog 85 will turn idly about its pivot 89, against theaction of a spring 90, toan ineffective position.

As the downward extension 82 of the stop engages the beveled side 84,the tappet 85 will be forced downwardly and the lever 86 turned aboutits pivot 91, thereby actuating, by means of a link 92, a bail 93mounted on a stud or stub-shaft 94 near the base of the machine. Thismovement of the bail 93 is effected against the resistance of a spring95, and causes the drawing to the right, looking from the front of themachine, of a link 96, thereby enabling the upward movement,

under the influence of a spring, not shown, of the rear arm 97 of alever 98 pivoted at 99. Upon such upward movement of the arm 97, theother arm 100 thereof will be swung downwardly, and, by engagement witha pin or stud l101 on the slide 62, will actuate the lever 59 and liftthe pin 58 to render the motor effective to actuate the general operator4.8. Upon the forward movement of the general operator, a cam-surface102 on the side adjacent the lever 98 will engage an off-set finger 103on the forward arm 100 of the lever, and swing the latter back to itsnormal position to enable it to be locked in its 'position by the link96, which is guided near its outer end by means not shown.

Each subtraction-stop 81 is provided with a cam-bar or extension 101,which, as the carriage moves into the corresponding subtraction-zone ina letter-feeding direction, engages the beveled face et a dog or tappet105 pivoted at 106 on a subtraction-trip lever 107, and rocks the latterabout its pivot 91, thereby lifting a link 108 and Swinging a bail 109connected thereto against the action of-a spring 110. This movement willalso effect movement to the right, viewed from the front, of atransversely-extending link 111, guided at its outer end by means notsliown,and withdraw the end of said link from the path of an arm 112 ofa threearmed lever 113, thereby permitting the latter to be swung in aclockwise direction about the axis of the shaft 66. The lever 113 isprovided with an upwardly-extending arm 114 normally in engagement witha finger 115 extending laterally from an arm 116 tixed on the shaft 66,and the movement of the lever 113 in a clockwise direction will actuatethe arm 116 and consequently the shaft 66. so as to withdraw the hook 67from engagement with the shoulder 68. The subtraction-bar will then bemoved to the rear by its spring 70a and the machine Set forsubtraction'. A forwardly-extending arm 117 of the lever 113 is providedwith a cam-surface 118, so that, upon the forward movement of thegeneral operator, the bar 49 thcreofwill engage the cam-surface 118 andrestore the lever 113 to its normal position, so that itsrearwardly-extending arm 112 may again be held in raised position by thelink 111. The mechanism described so far is similar in general to thatdisclosed in the patent to Minton, No. 1,280,065, granted September 24,1918.

Advantage may be taken of the fact that resetting of the subtraction-barmay be effected by the general operator, in carrying out the object oithe invention, namely, of insuring that the machine, if set forsubtraction. will be restored to addition when the carriage is backedinto a computing zone. Ordinarily, when the left-hand beveled face 88 ofthe tappet 85 is engaged by the downward extension 82 of one of thestops, the tappet will be rocked idly about its pivot. When, however,the machine is set for sub traction, the tappet 85 is. locked againstsuch swinging movement, so that the downward extensionp82 of a stop willexert a camming action on the beveled face 88, therebyvde pressing thetappet 85 and throwing the general operator into operation to restorethe machine to addition. For this purpose, the tappet 85 is providedwith a vertical slot 119, and the lever 107 is provided with a pin orprojection 120 normally lying above said slot, but which. upondepression of the tappet 105, will be carried into the slot 119, andwill prevent swinging oil the tappet 85 about its pivot when engaged byone of the downward extensions 82 during the return movement of thecarriage. it wiil be seen that the pin 120 has been cut away to form twofaces at a right angle with each other, so that change from ineffectiverelation to effective relation between pin 120 and dog 85 may beeffected quickly.

Obviously, when the tappet 105 is held in depressed position by thecam-bar 104, the tappet 85 will be locked against idle movement aboutits pivot, but, upon movement out of the subtraction-zone, the tappet105 will be released from the action of the cambar 104, and, unlessprovision is made of some other holding means, the tappet 85 will nolonger be locked against such idle movement. To retain the tappet 105 inlocking position, the link 111 is provided with a notch 121, and a frame122, comprising two parallel side plates 123, is pivoted at 124 on a xedpart of the machine. A hook or latch 125 is pivoted at 124 in the frame122, and is pressed by means of a spring 127 against the rear face ofthe link 111 at one side of the notch 121, so that, when the link iSdrawn to ineffective position` the latch 125 will drop into the notch121, and the link 111, by means of the bail 109 and link 108, willmaintain the lever 107 in actuated position, thereby retaining the pin120' in effective position in slot 119. When, therefore, the carriage isbackedinto another computing zone, the downward extension 82 of thecorresponding stop will depress the tappet 85 and trip the generaloperator.

Upon forward movement of the general operator, the fra-me 122, which hasbeen held in effective position by means of an arm or rod 128 fixed onthe frame 122, and engaging the rear end of one of the side bars of thegeneral operator, will be released to the. action of a spring 129, andthe upper end thereof will be swung rearwardly to the position shown inFigure 9, thereby releasing the link 111 and enabling thesubtractiontrip mechanism to return to its normal position. Upon thereturn of the general almenos operator. to its normal position, thetrame l 122 will be returned to its normal position lll (Figures 7 and8).

It will beevident that, in the mechanism so far described, if themachine is set for subtraction by means of the subtraction-hey 63, thetappet 105 will not be depressed and the machine will notbe reset foraddition when backed into a computing Zone. Provision must therefore bemade oi some means to actuate the subtraction-trip lever 107, andthereby loc-lr the tappet 85 against idle movement about its pivot. Forthis purpose, provision is made of a lil-shaped lever 130 pivoted on ashouldered screw 131 on a ixcd part of the machine, the normal positionot the lever being determined by a spring 132 attached at one end to thelever 130 by a screw 133, and at the other end to a iixed part of themachine by a screw v@ne arm of the 'tl-shaped lever is provided with acam-member 135 opposite the rear end ot the subtraction-bar 70, so that,upon movement of the latter to the rear, it will `force the member 135downward by a camming action, and rock the lever 130 about its pivot131. On the other arm of the lever provision is made oi a pivoted lever`136 having a hook 137 at its end farthest from the subtraction-bar, thelever 136 being urged to normal position by means of a spring` 138connecting it with the cam-member 135.

Upon movement of the subtraction-bar i0v to the rear, lever 130 will berocked thereby, and the secondary lever 136 moved to the right with thehook 137 on the lever 136 c11- gag'ing a pin or rod 139 fixed on thelink 111, thereby drawing the latter from its eliectivc position (Figure5) to an ineffective position {Figure 6l, and enabling the latch 125 todrop'into the notch 121. As shown in igure 6, the link 111 is moved pastthe position necessary for the latch 125 to drop into thc notch 121,and, in this additional movement, the advancing upturned end 140 of thesecondary lever 136 will strike a suitable stop or abutment 141, and thelever 136 will be swung suiciently to withdraw the hooi; 137 fromengagement with the rod 139, so that Ithe link 111 will be retained inineffective position by the latch 125 only. Upon movement of the hook137 to ineiiective position, as shown in Figure 6, the rod 139 may passover the hook 137 when the link 111 is released by the hook 125. The rod139 will, however, remain over the outer end of the hook 137, so that,upon movement oi the lever 130 to its normal position, ire-engagement ofthe book 137 and rod 139 will be sure to be effected. The Atappet 85 isthen locked against idle movement on its pivot, and, upon backing into acomputing zone, the general (perator will be thrown inio operation anthe mechanism restored to addition, as previously described.,

provided with an arm 143 to receive screw 1311 its outer end. rlhe stopor abutment 1111 may also .be formed by suitably cutting and bending a 4plate 1411, and this plate may be secured to the plate 142, with theabutment 1&1 projecting' over the upper edge oi the latter into the pathof the end 'ie-0 ot lever 136.

Variations may be resorted to within4 the scope of the invention, andportions oi' the improvements may be used without others.

Having thus described our invention, we claim:

1. 1n -a combined typewriting computting; machine, in combination,mechanism including; numeral-keys 'and a traveling carriage, computing'mechanism, normally set for addition, including a register,numeral-lrey-actuated means for indexing digits as typed, ageneralnperator -tor actuating the register in accordance with thedigits indexed, and subtractionsetting means, motor means for actuatingsaid general operator, addition and subtraction stops mounted on saidcarriage, a motor-triodevice engaged and actuated by said stops. duringmovement of the carriage in n letterfeeding direction, but ast Which'thestops normally pass idly in t e opposite directioi a subtraction-tripoperable by said carriage only in letter-feeding direction, and meanscontrolled by the subtraction-trip to render the motor-trip-deviceactuable by said stops when 'the carriage is backed across the rrachine.

2. In a motor-operated combined i2n writing and computing machine,settacle to subtraction, in combination, a carriage, addition andsubtraction Stops, settable at letter-space intervals along saidcarriage, a motor-trip-lever adjacent the path of said stops, a tappetpivotally mounted on said lever, so that, when engaged by vone of saidstops, in letter-feeding movement thereof, it will be held Xed on 'thelever and the latter will be actuated, but, when engaged during thereturn movement of the carriage, it will turn about its pivot toineffective position, and. a subtraction-trip-device, which, whenoperated, will prevent such turning of the tappet about its pivot andwill cause the motor-trip-lever to be actuated by said stops during'return movements of the carriage.

3. In a motor-operated combined typewriting and computing machine,settable 'to subtraction, in combination, a carriage, addition andsubtraction stops, settable at letter-space intervals along Saidcarriage, a

motor-trip-lever adjacent the path of said stops, a tappet pivotallymounted on said lever, so that, when engaged by one of said stops, inletter-feeding movement thereof, it will be held fixed on the lever andthe latter will be actuated, but, when engaged during the returnmovement of the carriage, it will be turned about its pivot toineffective position, a subtraction-trip device, which, when operated,will prevent such turning of the tappet about its pivot and Will causethe motor-trip-lever to be actuated by said stops during returnmovements of the carriage, and means to latch the subtraction-tripdevice in position to prevent movement of the tappet about its pivot.

4. In a motor-operated combined typewriting and computing machine,settable to subtraction, in combination, a carriage, means for yindexingdigits when typed, means including a general operator to compute numberswhen the digits thereof have been indexed, additionl and subtractionstops, settable at letter-space intervals along said carriage, amotor-trip-lever adjacent the'path of'said stops, a tappet pivotallymounted on said lever, so that, when engaged by one of said stops, in aletter-feeding movement thereof, it will be held fixed on the lever` andthe latter Will be actuated, but, when engaged during the returnmovement of the carriage, it Will be turned about its pivot toineffective position, a subtraction-trip device, which, when actuated,will, prevent such turning and enable actuation thereof by said stops inthe return movement of/ the carriage, means effective, upon operation ofthe Subtraction-trip device, tol latch the same in position to preventmovement of said tappet about its pivot, and means, whereby, uponoperation of the general operator, the latching means Will be renderedineffective.

5. In a combined typewriting and computing machine, in combination, acarriage, computing mechanism including a subtraction-setting memberyieldably urged to operate, a latch to prevent such operation, manualmeans to release said latch, carriage-controlled means having a one-wayconnection with said latch to release the same, and means actuable bysaid member, when released by said manual means, to operate saidcarriage-controlled means and then release .the same.

6. 'In a combined typewriting and computing machine, in combination, acarriage, computing mechanism including a subtraction-setting memberyieldably urged to operate, a latch to prevent such operation, manualmeans to release said latch carriagecontrolled means having a one-wayconi nection with said latch to release the same,

means actuable by said member, when released by said manual means, tooperate said carriage-controlled means and then release the same, and a'latching device to hold the carriage-controlled means in operatedcondition.

7 In a computing machine, in combination, digit-indexing means, ageneral operator to effect computation of numbers so indexed,subtraction-setting means, a lever urged to actuate thesubtraction-setting means, a reciprocable locking member to hold saidlever in ineffective position, and a device comprising a spring-pressedlatchlng member normally in engagement with said locking member, sothat, upon movement of the locking member to ineffective position, thelatching member will enter an opening therein and detain it in saidineffective position.

8. In a computing machine, in combination, digit-indexing means, agenera-l operator to effect computation of numbers so indexed,subtraction-setting means, a lever urged to actuate thesubtraction-setting means, a reciprocable locking member to hold saidlever in ineffective position, a device comprising a spring-pressedlatching member normally in engagement with said locking member, so asto enter an opening therein and detain it in ineffective position whenmoved thereto, and general-operatorcontrolled means to render the deviceeffective when the general operator is in normal position andlneffective when the general operator is moved therefrom.

9. In a computing machine, in combination, state-setting mechanismincluding a reciprocable bar urged in a direction to e1'- fect a changeof state, a device to hold said bar against movement in such direction,manually-operable means to render said ldevice ineffective, a memberhaving a one-way connection with said device to operate the same, andbeing urged in a direction to operate the device, a latch to preventsuch movement of the member, and means, Whereby, upon release of the barby said manually-operable means, the latch will be withdrawn toineffective position,

10. In a motor-operated computing machine, inl combination,subtraction-setting mechanism, a carriage, a stop positioned thereon, amotor-trip-lever, a tappet pivoted on said lever, an abutment on saidlever to support -said tappet, so that, when the latter is engaged bysaid stop. in a letter-space movement of the latter, the lever will beactuated, a spring normally maintaining the tappet against the abutment,but permitting it to be swung into ineffective position bythe stopduring the return movement of the carriage. and means actuable by saidsubtraction-setting mechanism, whereby the tappet will be locked'against movement away from said abutment, and, upon engagement thereofbythe stop in its return movement, the motor-trip-lcver will beactuated.

11. In a computing machine, in combination, digit-indexing means, ageneral operator to effect computation of numbers so indexed,subtraction-setting means, an operating member urged to actuate thesubtraction-setting means, a reciprocable locking member to hold saidmember in ineffective position, and a latching device for said iockingmember comprising a yieldingly-urged member normally in engagement withsaid locking member and holding said late-hing device ineffective, saidyieldingly-urged member being released by said locking member when thela-ter is moved to ineffective position, thereby rendering lsaidiatching device etfective.

12. In a power-operated computing machine, in combination, a carriage,an operating member mounted thereon, motor-trip mechanism including alever having an abutment thereon and a tappet pivoted nthereon andyieldingly pressed against said abutment, whereby said tappet, whenengaged by said member in a letter-feeding direction, will serve toactuate the lever, but, when engaged by the member in a reversemovement, will be swung about its pivot idly, and means to lock saidtappet against the abutment to enable the lever to be actuated by saidmember when the latter is moving in the reverse direction.

13. In a power-operated computing machine, in combination, a carriage,an operating member mounted thereon, motor-trip mechanism including alever having an abutment thereon and a tappet pivoted thereon andyieldingly pressed against said abutment, whereby said tappet, whenengaged by said member in the letter-feeding direction, will serve toactuate the lever, but, when engaged by the member in the reversemovement, will be swung about its pivot idly. said tappet having a, slottherein` and locking means for said tappet comprising a member to enterthe slot in the tappet and hold the latter against pivotal movement awayfrom the abutment.

14. In a power-operated computing machine, in combination, a carriage,an operating member mounted thereon, motor-trip mechanism including alever having an abutment thereon and a tappet pivoted thereon andyieldingly pressed against said abutment, whereby said tappet, whenengaged by said member in the letter-feeding direction, will serve toactuate the lever, but, when engaged by the member in the reversemovement, will be swung about its pivot idly, subtractionfsetting means,and means rendered effective by the subtraction-setting means forlocking said tappet against movement away from the abutment. so that thetappet, upon engagement by the member moving in the reverse direction,will serve to actuate the lever.

15. In a power-operated computing machine, in combination, a carriage,an operating' member mounted thereon, motor-trip mechanism including alever having an abutment thereon and a tappet pivoted thereon andyieldingly pressed against said abutment, whereby said tappet, whenengaged by said member in a letter-feeding direction, will serve toactuate the lever, but, when engaged by the member in a reversemovement, will be swung about its pivot idly, subtraction-settingmechanism, means rendered effective by the subtractionsetting mechanismfor locking said tappet against movement away from the abutment, so thatthe tappet, upon enga-gement by the member moving in the reversedirection, Will serve to actuate the lever, and means for detaining saidsubtraction-setting mechanism in operated condition.

16. In combination, a traveling carriage. a computing mechanism normallyfor addition, carriage-actuated means for de termining computing zones,subtraction.- setting means, means for restoring saidsubtraction-setting means to ineffective con.- dition, and means,effective only when the machine is set for subtraction, whereby backingof the carriage into a computingv zone will cause the restoring means tobe actuated.

17. In combination, a traveling carriage, computing mechanism normallyset for addition and including means for indexing numbers, and a generaloperator for effecting computation of the numbers so indexed,subtraction-setting means returnable to ineffective position by saidgeneral operator, controlling means effective, as the carriage passesout of a computing zone in lett-erfeeding direction, for automaticallythrowing said general operator into action, but normally ineffectivewhen the carriage is backed into said zone, and means whereby, when themachine is set for subtraction, said controlling means will be effectivewhen the carriage is backed into the computing zone.

18. In a combined typewriting and computing machine, in combination,means including a carriage for determining computing zones, computingmechanism normally set for addition, subtraction-setting means,manually-operable means for setting said subtraction-setting means,yieldablyurged means to actuate said subtraction-setting mea-ns andhaving a one-way connection therewith, a subtraction-trip devicenormally preventing operative movement of said yieldably-urged means andactuable b v said carriage only when the latter is moving in aletter-feeding direction, resetting means 'for said subtraction-settingmeans normally effective only when the carriage moves out of a computingzone in the letterfeeding direction, means whereby said subtraction-dripdevice, when actuated, Will render said re-setting means effective whenthe carriage is backed into a computing zone, and means wherebyactuation of said manually-operable means will render the resettingmeans effective When the carriage is backed into the computing zone.

19. In a combined typewriting and computing machine, in combination,computing mechanism settable for subtraction, motor means for actuatingsaid computing mechanism and re-setting the machine to addition at theend of said actuation, means, including a carriage, for determiningcomputing zones, means whereby the carriage Will start the motor meanswhen moved out of a computing zone in the letter-feeding direction, butwill be ineffective thereon in the return movement, and means wherebythe computing mechanism, when set for subtraction, will render thecarriage effective on the motor means in its return movement into acomputing zone.

20. In a combined typewriting and computing machine, in combination, acarriage, a subtraction-trip device actuable thereby,

subtraction-trip device to hold and a latching device normally held outof action by said subtraction-trip device, but effective thereon, uponoperation of the latter, to co-operate therewith and hold it in actuatedcondition.

21. In a combined typewriting and computing machine, in combination, acarriage, a subtraction-trip device actuable thereby, and means,independent of the carriage, rendered effective upon actuation of saidthe latter in actuated condition.

22. In a combined typewritingr and computing machine, in combination, acarriage, a. subtraction-trip device actuable thereby, a re-settingrtrip device normally actuable by the carriage at predetermined positionso-f the latter as it moves in a letter-feeding direction, and meanswhereby actuation of said subtraction-trip device will render saidre-setting device effective at the first of said predetermined positionspassed by the carriage in the return movement thereof.

FRANK K. DAVIS. CHARLES C. TAYLOR.

Witnesses GEORGE F. HAND, M. V. NICHOLS.

